Colorado Public Radio (http://bit.ly/1iWGoYK ) reports that 748 people were hospitalized as of Jan. 4, up from 263 as of Dec. 21.

At this time last year, 506 hospitalizations were reported.

Colorado is in the middle of one of its worst flu seasons since 2009 and a large number of those ending up in the hospital are young adults who usually aren’t as hard hit by the flu. Dr. Lisa Miller of the state health department says it’s not too late to get vaccinated.